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Previous Encounters (previous + encounter)
Selected AbstractsASSORTMENT AND THE EVOLUTION OF GENERALIZED RECIPROCITYEVOLUTION, Issue 7 2009Daniel J. Rankin Reciprocity is often invoked to explain cooperation. Reciprocity is cognitively demanding, and both direct and indirect reciprocity require that individuals store information about the propensity of their partners to cooperate. By contrast, generalized reciprocity, wherein individuals help on the condition that they received help previously, only relies on whether an individual received help in a previous encounter. Such anonymous information makes generalized reciprocity hard to evolve in a well-mixed population, as the strategy will lose out to pure defectors. Here we analyze a model for the evolution of generalized reciprocity, incorporating assortment of encounters, to investigate the conditions under which it will evolve. We show that, in a well-mixed population, generalized reciprocity cannot evolve. However, incorporating assortment of encounters can favor the evolution of generalized reciprocity in which indiscriminate cooperation and defection are both unstable. We show that generalized reciprocity can evolve under both the prisoner's dilemma and the snowdrift game. [source] The Effect of Capitation on Switching Primary Care PhysiciansHEALTH SERVICES RESEARCH, Issue 1p1 2003Melony E. S. Sorbero Objective To examine the relationship between patient case-mix, utilization, primary care physician (PCP) payment method, and the probability that patients switch their PCPs. Data Sources/Study Setting Administrative enrollment and claims/encounter data for 1994,1995 from four physician organizations. Study Design We developed a conceptual model of patient switching behavior, which we used to guide the specification of multivariate logistic analyses focusing on interactions between patient case-mix, utilization, and PCP reimbursement methods. Data Collection/Extraction Methods Claims data were aggregated to the encounter level; a switch was defined as a change in PCP since the previous encounter. The PCPs were reimbursed on either a capitated or fee-for-service (FFS) basis. Principal Findings Patients with stable chronic conditions (Ambulatory Diagnostic Groups [ADG] 10) and capitated PCPs were 36 percent more likely to switch PCPs than similar patients with FFS PCPs, controlling for patient age and sex and physician fixed effects. When the number of previous encounters was included in the model, this relationship was no longer significant. Instead high utilizers with capitated PCPs were significantly more likely to switch PCPs than were similar patients with FFS PCPs. Conclusions A patient's demographics and utilization are associated with the probability that the patient will switch PCPs. Capitated PCP payment was associated with higher rates of switching among high utilizers of health care resources. These findings raise concerns about the continuity and quality of care experienced by vulnerable patients in an era of changing financial incentives. [source] Knowledge of Jordanian mothers with regards to emergency management of dental traumaDENTAL TRAUMATOLOGY, Issue 6 2006Suhad H. Al-Jundi Abstract,,, Studies in Jordan indicated that delay in seeking emergency management of dental trauma leads to unfavorable outcome of even mild forms of trauma. The purpose of this cross-sectional study was to assess, by means of a structured questionnaire, the level of general knowledge of mothers in Jordan with regards to the immediate emergency management of dental trauma, and its relation to socioeconomic variables. The questionnaire surveyed mothers' demographic data, basic knowledge of immediate management of tooth fracture, avulsion, and loss of consciousness. It also investigated the participants self assessed knowledge, attitude to public education, and knowledge of availability and priority of emergency services for trauma in Jordan. The sample consisted of 2215 mothers who attended mother and child care centers in the capital Amman, and in Irbid (the second largest city in Jordan) over a period of 3 months (July to September, 2003). Overall the participants' basic knowledge with regards to the emergency management of the trauma cases presented in the questionnaire was deficient regardless of age, level of education, socioeconomic class, or number of previous encounters with dental trauma. Generally, the attitude to public education on the topic was positive and chi-square test indicated that the level of education of mothers positively affected their knowledge of ,during working hour' emergency services and the importance of immediate management of dental trauma. Educational programs that can be added to the mother and child care advice protocols may help improve the knowledge and awareness of mothers and therefore improve the outcomes of dental trauma. [source] Effects of plant and prey characteristics on the predatory behavior of Delphastus catalinaeENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2006Moshe Guershon Abstract Nymphal setosity of the whitefly Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) has been reported to be induced by mechanical stimuli such as leaf tomentosity, and related to the predatory performance of the coccinellid Delphastus catalinae (Horn) (Coleoptera: Coccinellidae). In this study, a possible adaptive value of this phenomenon for the whitefly is shown through the combined effects of leaf and prey characteristics on the walking and predatory behaviors of the beetle. Leaf tomentosity significantly affected the walking patterns of the beetle and therefore its searching abilities, thus indirectly increasing the influence of prey distribution upon predator's efficiency. Moreover, while searching on tomentose leaves, the beetles showed preference for the smooth prey phenotype. This behavior was found dependent on the experience of the beetle in previous encounters. These results are pertinent to intraspecific competition between the different nymphal phenotypes and to the predatory efficiency of this beetle, which is utilized in biological control of whiteflies. [source] Fine-tuning CD4+ central memory T cell heterogeneity by strength of stimulationEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 1 2008Vandana Kalia Abstract The memory T cell pool serves as a relatively long-lived heterogeneous repository of antigen-experienced T cells that "remember" previous encounters with antigen. While heterogeneity in the memory T cell pool is now well established, signals regulating the generation of this memory T cell heterogeneity are not fully understood. Two articles in this issue of the European Journal of Immunology highlight the importance of the strength of antigenic stimulation in regulating the generation of phenotypically and functionally distinct CD4+ T cell memory subsets. New insights are also provided into key molecular players that likely mediate differences in homeostatic and secondary expansion between the memory subsets. See accompanying articles: http://dx.doi.org/10.1002/eji200737611 and http://dx.doi.org/10.1002/eji200737852 [source] The Effect of Capitation on Switching Primary Care PhysiciansHEALTH SERVICES RESEARCH, Issue 1p1 2003Melony E. S. Sorbero Objective To examine the relationship between patient case-mix, utilization, primary care physician (PCP) payment method, and the probability that patients switch their PCPs. Data Sources/Study Setting Administrative enrollment and claims/encounter data for 1994,1995 from four physician organizations. Study Design We developed a conceptual model of patient switching behavior, which we used to guide the specification of multivariate logistic analyses focusing on interactions between patient case-mix, utilization, and PCP reimbursement methods. Data Collection/Extraction Methods Claims data were aggregated to the encounter level; a switch was defined as a change in PCP since the previous encounter. The PCPs were reimbursed on either a capitated or fee-for-service (FFS) basis. Principal Findings Patients with stable chronic conditions (Ambulatory Diagnostic Groups [ADG] 10) and capitated PCPs were 36 percent more likely to switch PCPs than similar patients with FFS PCPs, controlling for patient age and sex and physician fixed effects. When the number of previous encounters was included in the model, this relationship was no longer significant. Instead high utilizers with capitated PCPs were significantly more likely to switch PCPs than were similar patients with FFS PCPs. Conclusions A patient's demographics and utilization are associated with the probability that the patient will switch PCPs. Capitated PCP payment was associated with higher rates of switching among high utilizers of health care resources. These findings raise concerns about the continuity and quality of care experienced by vulnerable patients in an era of changing financial incentives. [source] | |||||||||||||